1. Field of the Invention
The present invention relates to a method for enhancing the efficacy of an agricultural chemical, an enhancer for an agricultural chemical, an enhancer composition for an agricultural chemical, and an agricultural chemical composition.
2. Description of the Related Art
Agricultural chemicals including insecticides, fungicides (or bactericides), herbicides, miticides (or acaricides) and plant growth regulators have been used in the forms of, for example, emulsions, wettable powders, granules, dusts and flowables. In the properties of these agricultural chemical preparations, various attempts have been made to achieve the maximum effectiveness of the agricultural chemicals. However, it has been difficult to enhance the effectiveness of agricultural chemicals through adjustments in formulations. It is further difficult to develop novel agricultural chemicals. Therefore, further enhancement of existing agricultural chemicals would highly contribute to the industry.
As substances capable of enhancing the effectiveness of agricultural chemicals, surfactants comprising various nitrogen-containing compounds such as quaternary ammonium salts, betaines and amine oxides have been known. It is known that quaternized or further polyoxyethylenated long-chain amines, among the above-mentioned compounds, are effective for this purpose. However, the enhancement effect of the above described compounds capable of enhancing the effectiveness of agricultural chemicals is not always satisfied.
Fatty acid alkanolamides are known substances and have been used as a foam stabilizer for a shampoo or the like. Further, it has also been known to use fatty acid alkanolamides in the field of agricultural chemicals. However, they are used for stabilizing agricultural chemicals in many cases. In particular, Japanese Patent Publication-A No. 58-118502 (published on Jul. 14, 1983) discloses the use of an alkylolamide nonionic surfactant as an auxiliary for an alkali cyanate herbicide; Japanese Patent Publication-A No. 58-128301 (published on Jul. 30, 1983) discloses an aqueous agricultural chemical suspension comprising an agricultural chemical which is difficultly soluble or insoluble in water as an active ingredient, a polyhydric alcohol nonionic surfactant such as a fatty acid alkanolamide, a thickener and others; Japanese Patent Publication-A No. 1-301605 (published on Dec. 5, 1989) discloses a dust or wettable powder for agricultural and horticultural uses which comprises a specific silane compound as an active ingredient and a nonionic surfactant such as a fatty acid alkylolamide; Japanese Patent Publication-A No. 2-142708 (published on May 31, 1990) discloses a dust for indoor use which comprises a pyrethroid compound and/or an organophosphorus compound as an active ingredient, a fatty acid alkylolamide and others; Japanese Patent Publication-A No. 3-48602 (published on Mar. 1, 1991) discloses the addition of a fatty acid alkanolamide to a foaming agent used in the foam-spraying of a pest control agent; Japanese Patent Publication-A No. 4-41406 (published on Feb. 12, 1992) discloses the use or a fatty acid alkanolamide as a stabilizer for a pyrethroid insecticide; and Japanese Patent Publication-B No. 63-41884 (published on Aug. 19, 1988) discloses that a fatty acid alkanolamide exhibits effective insecticidal and/or ovicidal activity against epizoa.